We investigated neural correlates when attending to a movement that could be made automatically in healthy subjects and Parkinson's disease (PD) patients. Subjects practiced a visuomotor association task until they could perform it automatically, and then directed their attention back to the automated task. Functional MRI was obtained during the early-learning, automatic stage, and when re-attending. In controls, attention to automatic movement induced more activation in the dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex, and rostral supplementary motor area. The motor cortex received more influence from the cortical motor association regions. In contrast, the pattern of the activity and connectivity of the striatum remained at the level of the automatic stage. In PD patients, attention enhanced activity in the DLPFC, premotor cortex, and cerebellum, but the connectivity from the putamen to the motor cortex decreased. Our findings demonstrate that, in controls, when a movement achieves the automatic stage, attention can influence the attentional networks and cortical motor association areas, but has no apparent effect on the striatum. In PD patients, attention induces a shift from the automatic mode back to the controlled pattern within the striatum. The shifting between controlled and automatic behaviors relies in part on striatal function.

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Exploring high performance cathode materials is essential to realize the adoption of Li-ion batteries for application in electric vehicles and hybrid electric vehicles. FeF 3 , as a typical iron-based fluoride, has been attracting considerable interest due to both the high electromotive force value of 2.7 V and the high theoretical capacity of 237 mA h g À1 (1e À transfer). In this study, we report a facile lowtemperature solution phase approach for synthesis of uniform iron fluoride nanocrystals on reduced graphene sheets stably suspended in ethanol solution. The resulting hybrid of iron fluoride nanocrystals and graphene sheets showed high specific capacity and high rate performance for iron fluoride type cathode materials. High stable specific capacity of about 210 mA h g À1 at a current density of 0.2 C was achieved, which is much higher than that of LiFePO 4 cathode material. Notably, these iron fluoride/ nanocomposite cathode materials demonstrated superior rate capability, with discharge capacities of 176, 145 and 113 mA h g À1 at 1, 2 and 5 C, respectively.

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Silicon nanostructures have been employed as the anodes of lithium-ion batteries to mitigate mechanical and chemical degradation. Conditions for averting fracture have been identified in terms of the Si critical size and its state of charge. Strong size dependencies were observed, and the critical sizes of fracture for different shapes of Si have been found to be: y90 nm for nanoparticles, y70 nm for nanowires, and y33 nm for nanofilms, below which the silicon nanostructures remain undamaged upon lithiation.

Extant research on strategic human resource management (SHRM) has primarily focused on the content of SHRM (best practices, bundles of practices, etc.) and its effect on firm performance. Little research has examined the SHRM process so as to better understand how SHRM is adopted and implemented and what impact it has on organizational processes and outcomes. This article examines the role of corporate culture in the SHRM adoption and implementation process. Empirical results from a sample of 223 Chinese enterprises indicate that corporate culture has an impact on the adoption of SHRM, and that different types of culture affect the SHRM process differently. Specifically, group and developmental cultures have positive effects on the adoption of SHRM, but the effect of hierarchical culture is not significant. Developmental culture is also found to have a direct effect on firm performance. This study offers significant implications for HRM in China and other dynamic and emerging economies. © 2008 Wiley Periodicals, Inc.

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Sodium-ion batteries have received great attention because of the abundant sodium resources and low cost. As a typical kind of cathode materials for Na-ion batteries, sodium manganese oxides have shown great potential in cathode application due to their high specific capacity and good rate capability. Herein, we successfully synthesized P2-type Na 0.4 Mn 0.54 Co 0.46 O 2 nanosheets via a two-step annealing route.The morphology and structure information of Na 0.4 Mn 0.54 Co 0.46 O 2 products were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM) technologies. The electrochemical performances of Na 0.4 Mn 0.54 Co 0.46 O 2 were measured by charge-discharge test, cyclic voltammogram (CV) and electrochemical impedance spectrum (EIS). As the cathode for Na-ion batteries, the layered Na 0.4 Mn 0.54 Co 0.46 O 2 nanosheets showed a high second charge capacity of 194 mAh/g and delivered a specific capacity of 125 mAh/g at a current of 20 mA/g after 60 cycles. 100 cycles at a rate of 2C) 30 . The available reversible capacity of P2-Na x [Fe 1/2 Mn 1/2 ]O 2 reaches 190 mAh/g with an average voltage of 2.75 V versus sodium metal 31 . The energy density is estimated to be 520 mWh/g, which is comparable to that of LiFePO 4 (about 530 mWh/g versus Li) and slightly higher than that of LiMn 2 O 4 (about 450mWh/g) 17,31 . The above research progress is proved that layered P2-type Co-doped sodium manganese oxides are promising cathode materials for Na-ion batteries. It is well know that reducing the manganese content and raising the average valence of manganese in the layered manganese-based cathode materials are effective ways to alleviate the manganese dissolution and Jahn-Teller effect. As we known, high sodium contents normally result in O3-type oxide cathodes, while low contents for P2-type ones with a higher capacity than O3-type 26,32,33 . Herein we have designed a layered Na 0.4 Mn 0.54 Co 0.46 O 2 cathode material with low sodium content for superior Na-ion batteries. The P2-Na 0.4 Mn 0.54 Co 0.46 O 2 have a good specific capacity and cycling performance at a current of 20 mA/g, and a specific capacity of 120 mAh/g is still achieved after 67 cycles. Experiment SectionMaterials synthesis： ： ： ：MnCO 3 was synthesized by a precipitation method. In a typical synthesis, 10 mmol Mn(NO 3 ) 2 was dissolved in 200 mL distilled water, then 200 mL of 0.5 mol/L NH 4 HCO 3 was added into the Mn(NO 3 ) 2 solution. Spherical Mn 2 O 3 was synthesized by annealing microsphere MnCO 3 at 400 °C for 10 h in air condition. The P2-Na 0.4 Mn 0.54 Co 0.46 O 2 cathode was synthesized by mixing 5 mmol Mn 2 O 3 , 5 mmol uniformity of spherical morphology. The pure phase of Mn 2 O 3 precursor can be clearly proved by the corresponding XRD patterns (Figure S1 in Supplementary information). The morphology and size of P2-Na 0.4 Mn 0.54 Co 0.46 O 2 particles can be also clearly observed from SEM images (Figure 3c,d), revealing that during the following high-tem...